Hot-air



(No Modem B. F. MGKINLEY.

HOT AIR ENGINE.

No. 356,146. Paten-mman. 18, 1887.

N. PETERS, Phaurlmugmpher, wnsnmgmn. D. C4

UNER

BENJAMIN F. MOKINLEY, OF CINCINNATI, OHIO.

HoT-Alai-:Nelne SPECIFICATION forming part of Letters Patent No. 356,145, dated January 18, 1887.

Application filed April 19, 1886.

fication My invention relates to a hot-air engine, and is designed to secure greater efficiency therein by increasing the cooling effect of a kcurrent of air upon the cooling-surface of the regenerating-chamber and upon the air contained within said chamber. It is especially adapted to be employed with a regeneratingchamber containing a displacer operated in succession with a working-piston in a cylinder in communication with said chamber, substantially as shown in Letters Patent No. 206, 597 granted me July 30, 1878. In engines of this class employing a current of normal air to cool the regeneratingchamber .upon its upper or cooling surfaces I have found that the radiant heat given off by these surfaces is not absorbed by the current of air, but is taken up by the outer casing of the engine or outer wall of the air-flue, and a large portion of it is radiated back again to the surfaces of the regenerating-chamber, thus lessening the efficiency of the engine. I have found by experiment that I'can take up or intercept this dark radiant heat by charging the current of air with aqueous vapor generated at a low temperature, and thus increase the efficiency of the engine by keeping the cooling-plates or other surfaces of the regenerating-chamber at alower temperature, all of which will be set forth in the description and drawing, making a part of this specification.

The drawing represents a vert-ical central section of 'a hot-air engine adapted to comprise my improvement.

A represents the upper or cooling disk of ,the regenerating-chamber, A', the lower or heating disk; B, the working-cylinder; D, the working-piston; O, the pitman.

I is an outer cylindrical casing surrounding the cylinder, the regenerating-chamber, and the entire lower portion of the engine, and opening only at its top immediately around the top of the working-cylinder. To the inside ofthe top part of the casing are attached Serial No. 199,434. (No model.)

concentric pendent iiangcsf, which descend into the channels of the upper corrugated disk, A. The space between this casing and the cylinder and disk A forms an inlet-flue, through which a current of air is carried, and, iowing down within this flue to near the bottom of the engine, passes through openings d into the ash-pan, and thence through the fire, taking up heat and the products of combustion and carrying them up against disk A', and thence through the space under said disk to flue S and uptake J to chimney, all substantially as set forth.

It is not essential that the cooling air-current shall be used to feed the fire; but when I so employ the aircurrent charged with vapor an additional benefit is received, for not only is the heat absorbed by the said current carried into and added to that of the combustion, but a still further benet arises from the fact that as the air-current charged with vapor passes through the fire it becomes heated into steam, which, being disassociated into its component gases, furnishes material for more perfect combustion. The more essential feature 0f my invention, however, is the use of the vapor to absorb tlre dark radiant heat given off by the upper disk, A, of the regenerating-chamber. The preferred method of accomplishing this is to slowly introduce water by pipe g (or other means) into the trough h, formed by the corrugation of disk A, near cylinder B. The disk A being heated by the current of hot air forced over its under sur.- face by the displacer E, gives off vapor at a low temperaturesay l00o to 2120 -which is absorbed bythe current of air entering the iiue and carried along with it over the upper side of said disk A. The vapor takes up or intercepts the dark radiant heat emanating from disk A, and prevents the outer case of the fine from receiving the heat and radiating it back again to the Walls of the regeneratingchamber, and also assists the air in cooling the same by contact, and thus cools the air within said chamber much more rapidly andy effectually than when the coolingcurrent is not charged with vapor.

The water is yproperly regulated by means of the cock fi, so that only a thin stratum is resting on the disk A to give off the vapor IOO regularly and rapidly. The water can, however, be introduced ont-o other portions of the disk A, or the air-current might be charged with vapor outside of the entrance-fine a without'ecting the essential feature of my invention. The essence of my invention is, one or more flues or ai r-passages so arranged With reference to the coolingsurface'of a hot-air engine as to cause a current of air charged with vapor to pass over and in close Contact With said cooling-surfaces, and without reference to any special form of construction or to any particular method of producing the current of air or of charging the same with vapor.

I claiml. In a hot-air engine, the cooling portion of the regeneratingchamber, in combination With a flue, and cooled by passing through said flue a current of air charged with aqueous vapor, substantially as specified.

2. A hot air engine employing a regenerat' ingehamber, in combination with a coolingi Y flue, and provided with a body of heated wa- 8. A hot-air engine having a regenerating chamber, one portion of which is cooled by a current of air charged with aqueous vapor by coming in contact with the surfaces of said regeneratiugchamber, substantially as speciiied.

4. A hot-air engine employing a regenerating-chamber, and having au air-cooling iiue and a body of water heated by said engine, by means of which the current of cooling air is saturated on its entranceinto said flue, wherebythe radiant heat of the regenerating-chamber is taken up by said aqueous Vapor and the surfaces cooled by the air Contact, substantially as specied.

5. A bot-air engine employing a regenerating-chamber and one or more air-nues supplied by a current of normal air charged with aqueous vapor upon its entrance into the airflue, whereby the surfaces of the air-Hue and Y BENJAMIN F. MCKINLEY.

Witnesses:

ROBERT ZAHNER, M. E. MILLIKAN. 

